1. Field of the Invention
This invention is generally directed to safety guards for use with radial arm saws and, more particularly, to pivotable blade guards for protecting the lower edge of the cutting blade of a radial arm saw which are normally locked in a covering relationship with respect to the cutting blade unless manually released so that the lower guards elevate automatically by engagement of a workpiece in either a rip cut or crosscut mode.
2. History of the Related Art
Radial arm saws include a saw assembly mounted on a horizontal supporting arm positioned above a work table. The saw assembly is pivotal relative to the supporting arm to enable the saw to be selectively used in crosscutting or rip cutting modes. During crosscutting, the length of the workpiece is changed by making straight or angled cuts. The width of the workpiece is changed during rip cutting by cutting along its length. The saw is moved relative to a stationary workpiece during crosscutting, while the workpiece is moved relative to a stationary saw during rip cutting.
Both crosscutting and rip cutting have associated safety hazards due to the inherently dangerous nature of these operations. Crosscutting hazards include operator exposure to the rotating saw blade, rolling carriage and projected workpieces. These hazards pose chances of serious bodily injury to operators.
Rip cutting similarly exposes the operator to bodily injury due to contact with the rotating blade. Other hazards of rip cutting include workpiece kickback and wrong way feeding of the workpiece.
Thus, there is a need for a saw blade guard suitable for use on radial arm saws that provides reliable operator protection during both crosscutting and rip cutting operations.
Some examples of prior art safety guards for radial arm and circular type saws are disclosed in U.S. Pat. Nos. 1,127,509 to Pleasance, 4,672,746 to Zeilenga, 5,287,779 to Metzger, Jr. and 5,287,780 to Metzger, Jr. et al. as well as British Patent No. 966,075.